The invention relates to an agricultural implement according to the preamble of claim 1.
A ground working implement with hydraulically actuated supporting wheel is known from the German application DE 10 2012 016 348 A1. In order to relieve the towing tractor of a part of the weight of the implement in the lifted position, the support wheel may be pressed hydraulically to the ground and thus carry part of the weight of the implement. This improves the steering ability of the towing tractor. To ensure that the support wheel does not leave any tracks in the ground during operation, this may also be lifted hydraulically above the ground surface. However, the hydraulic support wheel must be operated separately via a control valve during the lifting operation of the implement.
German patent application DE 10 2013 007 038 A1 uses a mechanical solution, wherein a weight fraction of a heavy packer roller is transferred to a support wheel via a four-point linkage. In the lowered state, the support wheel arm is pushed upwards due to the weight of the implement, so that the support wheel likewise does not leave any tracks in the ground being worked. However, the effectiveness of the support wheel to relieve loading on the front axle of the tractor varies with different roller weights. The front part of the implement must also be carried by the towing vehicle.
The object of the present invention is to relieve the towing vehicle of a part of the implement weight without actuating further additional hydraulic devices, as well as leaving the ground surface free of any tracks behind the implement in the working position.
This object is achieved by the features of the characterizing part of claim 1.
At least one support wheel on the ground working implement in conjunction with an energy accumulator is provided by the vertically movable arrangement, which can move into two positions via a dead center position, while, in a lowered implement position which preferably corresponds to the working position, the placing of the support wheel on the ground subjects the energy accumulator to supporting energy and is displaced through its dead center position so that the energy accumulator, after passing through this position, lifts the support wheel with its stored energy above the ground. If the ground working implement is lifted by the towing vehicle, the energy accumulator passes through its dead center position in the opposite direction by means of an articulated linkage arrangement and presses the support wheel against the ground surface with a supporting force in the raised implement position. Since the energy accumulator is also supported against the frame of the ground working implement, part of the implement weight is supported by the support wheel. The lifting force requirement of the towing vehicle is reduced, thus improving its steering ability.
Optimum energy utilization is achieved by arranging the line of action of one or more energy accumulators on an imaginary line or plane, which runs through the counter bearings or their bearing points or bearing axles. Several energy accumulators may be connected in parallel or in series. A multiple counter bearing arrangement with respectively associated energy accumulators is also conceivable, for example on the right and left or above and below the wheel arm.
By connecting the wheel arm to the frame of the ground working implement, on the one hand, as well as with the energy accumulator and one or more deflection mechanisms, on the other hand, one achieves an effective design, wherein the energy accumulator may be positioned in more favorable installation spaces in order not to interfere with the effect of ground working tools.
The deflection mechanism also provides a further possibility for representing transmission ratios and other kinematic dependencies between the frame, the energy accumulator and the movable wheel arm.
Different implement weights or equipment variants may be compensated for by using an energy accumulator with adjustable preloading.
In this way, energy accumulators with a progressive, linear or degressive characteristic may be used.
The energy accumulator may be configured in one or more parts in order to store different characteristics. In addition, a combination of different spring types, as mentioned above, is also conceivable in a linkage, as well as a spatially separated construction.
In addition to conventional springs, elastomer springs, piston-cylinder springs or bellows springs with optionally coupled pressure or energy accumulators are included. If the energy accumulator is formed as a fluid cylinder with a pressure accumulator connected thereto, an effective and compact design is also possible. Combining this system with a pressure supply and the necessary valves, provides for a comfortable and variable adjustment of the support and lifting forces.
The displacement of at least one counter bearing, as occurs, for example, during the passage of the dead center position, may be assisted or only released by a further auxiliary device, which is triggered by an external force. For example, this auxiliary device may be actuated by raising the implement or by lowering a support roller, and thus, depending on the position, the energy accumulator or at least one of its counter bearings may be shifted from a raised position to a working position and inversely, and/or secured there.
When the auxiliary device is operatively connected directly to the lifting device of the towing vehicle, the energy accumulator or its counter bearing is displaced, for example, by applying an upper linkage force, while its effect for lifting or lowering the support wheel is coupled with the lifting movement of the towing vehicle. This particularly facilitates the working sequence upon turning at the headland to be worked.
As the auxiliary chassis is also designed as a function of a reconsolidation device for the worked ground, a further multiple use is achieved. The auxiliary chassis may then also be used in the working position of the device for depth guidance of the same. The lifting force acting on the auxiliary chassis then acts as a holding force via the frame on the ground working implements at the front, and is used precisely in heavy ground conditions to ensure the working quality of the implement. Agricultural implements with a large working width are often provided with a multipart foldable base frame in order to achieve good ground adaptation, on the one hand, and an acceptable width for road transport, on the other hand. In such a configuration, the auxiliary chassis and its components, in addition to energy accumulators, are preferably arranged at a central region of the frame, so that the function and advantages of the invention are retained even in the case of laterally-foldable frame parts. Preferably, the devices for the depth guide of the implement pivot with the side parts of the foldable or pivotable frame.
The invention is distinguished in particular by the fact that, by utilizing the lifting forces or lifting movement of a towing vehicle, an energy accumulator of an agricultural implement is displaced in its linkage in such a way that a part of the implement weight is transmitted via the energy accumulator to an auxiliary chassis in the lifted state of the implement, thus relieving the towing vehicle and, in the working position, relieving or lifting the auxiliary chassis via the same energy accumulator, and thus reducing or avoiding any disturbing influences of the auxiliary chassis on the work implement.
Further details and advantages of the subject matter of the invention are given in the following description and the accompanying drawings in which an exemplary embodiment with the necessary details is shown: